The invention relates generally to structures for supporting a display apparatus, such as a color television picture tube, within an enclosure, such as a cabinet, having at least one speaker and, more particularly, to mounting lugs which provide greater support to the color television picture tube and a reduction in microphonics to certain of the components within the tube induced by the acoustical vibration of the speaker.
A cathode ray tube (CRT), such as a color television picture tube, is evacuated to a very low pressure and accordingly is subject to the possibility of implosion due to the stresses produced by atmospheric pressure acting on all surfaces of the tube. This problem has been addressed in the art by providing the CRT with an implosion protection band, which circumscribes the faceplate of the tube and applies a compressive force thereto. Mounting lugs, either integral with, or attached to the implosion protection band are used to support the tube within the cabinet. Typically, the mounting lugs are positioned at the corners of the tube and have an attachment surface disposed perpendicular to the sidewall of the faceplate and aligned along the faceplate diagonals. Bolts, screws or equivalent hardware extend through openings in the mounting surfaces of the lugs to attach the tube to mounting bosses in the cabinet. This effectively couples the tube to the cabinet along the longitudinal, or Z-axis of the tube. In a cabinet having front-mounted speakers, the acoustical vibration of the speakers induces a maximum vibration to the tube and its internal components, especially the color selection electrode, in the Z-axis direction. Additionally, during transporting of the display apparatus, mishandling occasionally occurs, for example if the apparatus is dropped. If the drop occurs with the CRT in a xe2x80x9cneck downxe2x80x9d orientation, the mounting lugs may be bent resulting in a gap between the bezel of the enclosure and the tube. If conductive material is inadvertently inserted into this gap it is possible that electrical contact with portions of the tube that operate a high voltage could occur.
A display apparatus comprises at least one speaker and a cathoderay tube (CRT) secured within an enclosure to a plurality of mounting bosses. The cathode-ray tube has an evacuated envelope with a substantially rectangular-shaped faceplate panel having four corners and a viewing portion extending to a peripheral sidewall. The viewing portion has a luminescent line screen on the interior surface thereof. The viewing portion including two orthogonal axes, a major axis parallel to a longer dimension of the viewing portion and a minor axis parallel to a smaller dimension of the viewing portion. The CRT has therein an electron gun, capable of generating at least one electron beam, aligned along a central longitudinal axis of the CRT that is perpendicular to the major and minor axes. The CRT also has a color selection electrode in proximity to the interior surface of the viewing portion of the faceplate. An implosion protection band extends around the sidewall of the faceplate panel. At least four mounting lugs, each having a base portion and an attachment portion with a mounting aperture therethrough, cooperate with the implosion protection band to facilitate securing the CRT within the enclosure. The attachment portion of each of the mounting lugs is aligned along the central longitudinal axis of the tube and parallel to at least one of the two orthogonal axes to strengthen the attachment portion and reduce microphonics induced by the speaker.